The icon of South Indian cinema was admitted in Sri Ramachandra Medical Centre here on Sunday last.
The Tamil actor has been undergoing dialysis and has kidney problems.
Rajinikanth has been suffering from recurrent respiratory infection and gastro intestinal ailments and was advised complete bed rest.
The 61-year-old star with a God like fan following after the phenomenal success of ROBOT (ENDHIRAN), which was dubbed in Hindi as well, had recently started working on his new film RANA with Deepika Padukone in Chennai.
He plays three roles in the film on the Mahurat sets of which he fell sick on April 29 and had to be hospitalized first.